JP7138189B2 - Medical device with pressure sensor - Google Patents

Description

The present disclosure relates to medical devices and methods for manufacturing medical devices. More specifically, the present disclosure relates to blood pressure sensing guidewires and methods for using pressure sensing guidewires.

A wide variety of internal medical devices have been developed for medical applications, such as intravascular use. Some of these devices include guidewires, catheters, and the like. These devices can be manufactured by any one of a variety of different manufacturing methods and used according to any one of a variety of methods. Known medical devices and methods each have certain advantages and disadvantages. There continues to be a need to provide alternative medical devices and alternative methods for making and using medical devices.

Japanese Patent Publication No. 2016-510679

This disclosure provides alternatives for the design, materials, methods of manufacture, and use of medical devices. A pressure sensitive medical device is disclosed. A pressure sensitive medical device includes a tubular member having a proximal region and a housing region; an optical fiber disposed within the tubular member and extending to the housing region, the optical fiber having a distal end region having a cavity formed therein; a polymeric member disposed within the cavity; and a reflective surface disposed along the polymeric member.

Alternatively or additionally to any of the above embodiments, the proximal region of the tubular member has a first inner diameter, the housing region of the tubular member has a second inner diameter, the first inner diameter different from the inner diameter of 2.

Alternatively or additionally to any of the above embodiments, the first inner diameter is smaller than the second inner diameter.
Alternatively or additionally to any of the above embodiments, the tubular member has a substantially constant outer diameter.

Alternatively or additionally to any of the above embodiments, the optical fiber has a substantially constant outer diameter.
Alternatively or additionally to any of the above embodiments, one or more fiber Bragg gratings are arranged along the optical fiber.

Alternatively or additionally to any of the above embodiments, the polymeric member substantially fills the cavity.
Alternatively or additionally to any of the above embodiments, the reflective surface includes a coating disposed along the polymeric member.

Alternatively or additionally to any of the above embodiments, the coating comprises a metal.
Alternatively or additionally to any of the above embodiments, a coating is disposed on the distal end of the polymeric member.

A pressure sensing guidewire is disclosed. The pressure sensing guidewire comprises a tubular member having a proximal region and a pressure sensor housing region; an optical fiber disposed within the tubular member and extending to the pressure sensor housing region; the pressure sensor filled with a polymer at the distal end region of the optical fiber. and a reflective coating disposed along at least a portion of the pressure sensor.

Alternatively or additionally to any of the above embodiments, the proximal region of the tubular member has a first inner diameter, the pressure sensor housing region of the tubular member has a second inner diameter, and the first inner diameter is different from the second inner diameter.

Alternatively or additionally to any of the above embodiments, the first inner diameter is smaller than the second inner diameter.
Alternatively or additionally to any of the above embodiments, the tubular member has a substantially constant outer diameter.

Alternatively or additionally to any of the above embodiments, the optical fiber has a substantially constant outer diameter.
Alternatively or additionally to any of the above embodiments, one or more fiber Bragg gratings are arranged along the optical fiber.

Alternatively or additionally to any of the above embodiments, the reflective coating comprises a metal.
Alternatively or additionally to any of the above embodiments, a reflective coating is disposed on the distal end of the pressure sensor.

Alternatively or additionally to any of the above embodiments, the proximal region of the tubular member has a first inner diameter, the pressure sensor housing region of the tubular member has a second inner diameter, and the first inner diameter is less than the second inner diameter and the tubular member has a substantially constant outer diameter.

A method of manufacturing a pressure-sensing guidewire is disclosed. The method includes forming a cavity along a distal end region of the optical fiber; placing a polymeric member within the cavity; bonding a reflective member to the polymeric member to form a pressure sensor; Disposing a pressure sensor within the housing area.

Alternatively or additionally to any of the above embodiments, further comprising disposing one or more fiber Bragg gratings along the optical fiber.
The above summary of some embodiments is not intended to describe each disclosed embodiment or every implementation of the present disclosure. The drawings and detailed description that follow more particularly exemplify these embodiments.

The present disclosure can be more fully understood upon consideration of the following detailed description in conjunction with the accompanying drawings.
1 is a partial cross-sectional side view of a portion of an exemplary medical device; FIG. 1 is a partial cross-sectional view of an exemplary medical device positioned at a first position adjacent an endovascular occlusion; FIG. FIG. 3 is a partial cross-sectional view of an exemplary medical device positioned at a second position adjacent to an endovascular occlusion; 1 illustrates a portion of an exemplary medical device; 1 illustrates a portion of an exemplary medical device;

While the disclosure is susceptible to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure.

DETAILED DESCRIPTION For the terms defined below, those definitions shall apply unless different definitions are provided in the claims or elsewhere in this specification.

In this application, all numerical values are to be modified with the term "about," whether or not explicitly indicated. The term "about" generally refers to a range of numbers that one skilled in the art would consider equivalent to the stated value (eg, having the same function or result). In many cases, the term "about" can include numbers rounded to the nearest significant figure.

The recitation of numerical ranges by upper and lower limits includes all numbers within that range (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).
As used in this specification and the appended claims, the singular forms "a,""the," and "said" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally used in its sense including "and/or" unless the content clearly dictates otherwise.

References herein to "embodiments," "some embodiments," "other embodiments," etc. may mean that the described embodiments have one or more particular features, structures, and/or characteristics. Note that we indicate that we can include However, such a description does not necessarily mean that all embodiments will include the particular features, structures, and/or properties. Further, where specific features, structures and/or properties are described in the context of one embodiment, such functions, structures and/or properties are not expressly stated to the contrary. It should be understood that it can be used in connection with other embodiments as well, whether explicitly stated or not.

The following detailed description should be read with reference to the drawings, in which similar elements in different drawings are numbered the same. The drawings, which are not necessarily to scale, depict exemplary embodiments and are not intended to limit the scope of the invention.

During some medical interventions, it may be desirable to measure and/or monitor intravascular blood pressure. For example, some medical devices may include pressure sensors that allow clinicians to monitor blood pressure. Such devices may be useful in determining coronary fractional flow reserve (FFR). FFR may be understood as post-stenotic pressure relative to pre-stenotic pressure (and/or aortic pressure).

FIG. 1 shows a portion of an exemplary medical device 10. As shown in FIG. In this example, medical device 10 is a blood pressure sensing guidewire 10 . However, this is not intended to be limiting, as other medical devices are also contemplated. For example, medical device 10 may include various devices including catheters, shafts, leads, wires/guidewires, etc., and/or devices designed for use in vascular regions, body lumens, and the like. As discussed herein, a medical device may include sensors (eg, sensor 20) that may be utilized to measure pressure and/or temperature. In some of these and other examples, a sensor (eg, sensor 20) may be used in combination with ultrasound, optical coherence tomography, optoacoustic imaging, and the like.

Guidewire 10 may include a shaft or tubular member 12 . Tubular member 12 may include proximal region 14 and distal region 16 . The materials of proximal region 14 and distal region 16 can vary and can include materials disclosed herein. For example, distal region 16 may comprise a nickel-cobalt-chromium-molybdenum alloy (eg, MP35-N). Proximal region 14 may be made from the same material as distal region 16 or a different material such as stainless steel. These are just examples. Other materials are also conceivable.

In some embodiments, proximal region 14 and distal region 16 are formed from the same unitary material. In other words, proximal region 14 and distal region 16 are portions of the same tube that defines tubular member 12 . In other embodiments, proximal region 14 and distal region 16 are separate tubular members that are joined together. For example, a portion of the outer surface of portions 14/16 can be removed and sleeve 17 can be placed over the removed portion to join regions 14/16. Alternatively, sleeve 17 may simply be placed over regions 14/16. Other bonding can also be used, including welding, thermal bonding, adhesive bonding, and the like. When sleeve 17 is used to join proximal region 14 with distal region 16 , sleeve 17 may include a material that desirably bonds with both proximal region 14 and distal region 16 . For example, sleeve 17 may comprise a nickel-chromium-molybdenum alloy (eg, INCONEL®).

A plurality of slots 18 may be formed in tubular member 12 . In at least some embodiments, slot 18 is formed in distal region 16 . In at least some embodiments, proximal region 14 lacks slots 18 . However, proximal region 14 may include slots 18 . Slots 18 may be desirable for several reasons. For example, slots 18 can provide tubular member 12 with a desired level of flexibility (eg, along distal region 16) while also allowing for adequate transmission of torque. Slots 18 may be arranged/distributed along distal region 16 in any suitable manner. For example, slots 18 may be arranged in pairs of opposing slots 18 distributed along the length of distal region 16 . In some embodiments, pairs of adjacent slots 18 may have substantially constant spacing from each other. Alternatively, the spacing between adjacent pairs may vary. For example, more distal regions of distal region 16 may have reduced spacing (and/or increased slot density), which may provide greater flexibility. In other embodiments, more distal regions of distal region 16 may have increased spacing (and/or decreased slot density). These are just examples. Other arrangements are also possible.

A sensor 20, which may take the form of a pressure sensor 20, may be disposed within tubular member 12 (eg, within the lumen of tubular member 12). Although the pressure sensor 20 is shown schematically in FIG. 1, it is understood that the structural form and/or type of the pressure sensor 20 may vary. For example, pressure sensor 20 may be a semiconductor (e.g., silicon wafer) pressure sensor, a piezoelectric pressure sensor, a piezoresistive pressure sensor, a capacitive pressure sensor, a fiber optic or optical pressure sensor, a Fabry-Perot pressure sensor, an ultrasonic transducer. and/or may include ultrasonic pressure sensors, magnetic pressure sensors, solid state pressure sensors, etc., or any other suitable pressure sensor. In some of these and other examples, sensor 20 may take the form of or be a temperature sensor, a flow sensor, an acoustic sensor, an ultrasonic sensor, or the like. These types of sensors can be utilized in any of the devices disclosed herein within reasonable limits.

As noted above, pressure sensor 20 may include an optical pressure sensor. In at least some of these embodiments, an optical fiber or fiber optic cable 24 (eg, a multimode optical fiber) can be attached to pressure sensor 20 and may extend proximally therefrom. Optical fiber 24 may include a central core 60 and an outer cladding 62 . In some examples, a sealing member (not shown) may attach optical fiber 24 to tubular member 12 . Such attachment members may be mounted circumferentially around optical fiber 24 and may be secured to the inner surface of tubular member 12 (eg, distal region 16). Alternatively, the centering member 26 may be glued to the optical fiber 24 . In at least some embodiments, centering member 26 is spaced proximally from pressure sensor 20 . Other arrangements are also possible. Centering member 26 may help reduce forces that pressure sensor 20 may be exposed to during guidewire navigation and/or use.

In at least some embodiments, distal region 16 may include a region with thin walls and/or an increased inner diameter that defines sensor housing region 52 . Sensor housing region 52 is generally the region of distal region 16 that ultimately “houses” pressure sensor 20 . A portion of the inner wall of tubular member 12 may be removed at sensor housing area 52 to create or define additional space in which sensor 20 may be accommodated. Sensor housing region 52 may include one or more openings such as one or more distal porthole openings 66 that provide fluid access to pressure sensor 20 .

A tip member 30 may be coupled to distal region 16 . Tip member 30 may include a core member 32 and a spring or coil member 34 . A distal tip 36 may be attached to core member 32 and/or spring 34 . In at least some embodiments, distal tip 36 can take the form of a solder ball tip. Tip member 30 may be joined to distal region 16 of tubular member 12 with a joining member 46, such as a weld.

Tubular member 12 may include an outer coating 19 . In some embodiments, coating 19 can extend along substantially the entire length of tubular member 12 . In other embodiments, one or more separate sections of tubular member 12 may include coating 19 . Coating 19 may be a hydrophobic coating, a hydrophilic coating, or the like. Tubular member 12 may also include an inner coating 64 (eg, a hydrophobic coating, a hydrophilic coating, etc.) disposed along its inner surface. For example, hydrophilic coating 64 may be disposed along the inner surface of housing region 52 . In some of these and other examples, core member 32 may include a coating (eg, a hydrophilic coating). For example, the proximal end region and/or the proximal end of core member 32 may include a coating. In some of these and other examples, pressure sensor 20 may also include a coating (eg, a hydrophilic coating).

In use, a clinician can use guidewire 10 to measure and/or calculate FFR (eg, pre-occlusion pressure and/or post-occlusion pressure relative to aortic pressure). Measuring and/or calculating FFR may include measuring the patient's aortic pressure. This may involve advancing the guidewire 10 through the vessel or body lumen 54 to a location proximal or upstream of the occlusion 56, as shown in FIG. For example, guidewire 10 is advanced through guide catheter 58 to a position where at least a portion of sensor 20 is disposed distal to the distal end of guide catheter 58 to measure pressure within body lumen 54 . be able to. This pressure can be characterized as the initial pressure. In some embodiments, aortic pressure can also be measured by another device (eg, pressure-sensing guidewire, catheter, etc.). The initial pressure can equal the aortic pressure. For example, the initial pressure measured by guidewire 10 may be set to be the same as the measured aortic pressure. The guidewire 10 can be further advanced to a position distal or downstream of the occlusion 56 to measure pressure within the body lumen 54, as shown in FIG. This pressure can be characterized as downstream pressure or distal pressure. FFR can be calculated using distal pressure and aortic pressure.

FIG. 4 illustrates another exemplary medical device 110 that may be similar in form and function to other medical devices disclosed herein. Medical device 110 may include tubular member 12 (eg, including structural features described and shown herein). Optical fiber 124 may be disposed within tubular member 12 . Optical fiber 124 may include core 160 and cladding 162 . In some examples, a single mode optical fiber having an outer diameter of approximately 125 μm (eg, an additional 62.5 μm core 160) may be used. In another example, a multimode optical fiber having an outer diameter of approximately 125 μm (eg, an additional 62.5 μm core 160) may be used. In another example, a single mode optical fiber having an outer diameter of approximately 125 μm and a core 160 of 62.5 μm may be spliced with another optical fiber having an outer diameter of 125 μm and a core 160 of 105 μm. In this example, an optical fiber with a larger core 160 can be used to form/define a sensor (eg, sensor 120 as discussed herein). In another example, a multimode optical fiber having an outer diameter of approximately 125 μm and a core 160 of 62.5 μm may be spliced with another optical fiber having an outer diameter of 125 μm and a core 160 of 105 μm. In this example, an optical fiber with a larger core 160 can be used to form/define a sensor (eg, sensor 120 as discussed herein). These are just examples. Various sizes of optical fibers are possible.

Pressure sensor 120 may be formed at the distal end region of optical fiber 124 . In this example, pressure sensor 120 may be defined by forming a depression or cavity 168 in optical fiber 124 and then placing polymer member 170 within cavity 176 . In other words, the pressure sensor 120 can be formed without requiring a separate glass or micro-optic-mechanical system (MOMS) housing with deflectable membranes. Alternatively, an elastic material with a low modulus and high feel can be placed in cavity 168 to define pressure sensor 120 . The use of pressure sensor 120 formed at the end of optical fiber 124 may be desirable for several reasons. For example, polymer member 170 may be relatively sensitive to pressure changes. This can provide pressure sensor 170 with a high level of sensitivity. Further, by not having a separate sensor housing attached to the end of the optical fiber 124, the overall size of the medical device 110 may be reduced (e.g., because the tubular member 12 need not contain a sensor housing). can be at least partially smaller). In at least some examples, polymer member 170 can extend to the bottom (eg, proximal end) of cavity 168 . Polymer member 170 may then contact some or all of the proximal end or edge of cavity 168 . Polymer member 170 may extend distally and fill some or all of cavity 168 . In some cases, a portion of polymer member 170 may extend distally beyond the distal end of optical fiber 124 . In other examples, the polymer member 170 can terminate at the distal end of the optical fiber 124 (eg, the polymer member 170 and the optical fiber 124 are coextensive and bound together).

In some examples, the polymer member 170 is dry film photosensitive material such as Ordyl SY300, ADEX/SY300, or SU-8, liquid photosensitive material such as SU-8, polyimide (eg, film or liquid photosensitive material), benzo Cyclobutene, various non-photosensitive polymer films such as polyethylene terephthalate, cyclic olefin copolymers, Kapton®, polydimethylsiloxane, poly(methyl methacrylate), and the like. Other materials are also contemplated, including those disclosed herein.

In some examples, polymer member 170 may be temperature sensitive. This allows sensor 120 to additionally or alternatively function as a temperature sensor. In some examples, one or more fiber Bragg gratings 172 can be placed along the optical fiber 124 . Fiber Bragg gratings may allow temperature compensation.

A reflective member or coating 174 may be coupled to the polymeric member 170 . In some examples, coating 174 can include metals, polymers such as parylene, vapor deposition materials (eg, oxides, nitrides, carbon materials, etc.), and the like. In some examples, coating 174 can include mirrors or partial mirrors that can be formed by sputtering a reflective material, such as chromium, silver, zirconium dioxide, titanium dioxide, along polymer member 170 . In some examples, coating 174 can take the form of a single layer of material. Alternatively, coating 174 may include two or more separate and distinct layers of material (including the same or different materials).

In some examples, cavity 168 may have depth D1. In some examples, depth D1 can be on the order of about 1 μm to 100 μm. However, the depth can vary. For example, FIG. 5 illustrates another exemplary medical device 210 that may be similar in form and function to other medical devices disclosed herein in which the depth D2 of cavity 268 varies. In this example, medical device 210 can include optical fiber 224 having cavity 268 formed therein. Cavity 268 may have a depth D2 on the order of approximately 100 μm to 500 μm. By changing the depth of the cavity 168/268, the sensitivity can be changed.

Similar to medical device 110, medical device 210 may include tubular member 12 (eg, including structural features described and shown herein). An optical fiber 224 can be disposed within the tubular member 12 and can include a core 260 and a cladding 262 . Pressure sensor 220 may be formed at the distal end region of optical fiber 224 . In this example, pressure sensor 220 may be defined by cavity 268 within optical fiber 224 and polymer member 270 disposed within cavity 276 .

Medical device 210 may include other features similar to medical device 110 . For example, in some examples one or more fiber Bragg gratings 272 may be disposed along the optical fiber 224 . A reflective member or coating 274 may be coupled to the polymeric member 270 . In some examples, coating 274 may include metals, polymers such as parylene, vapor deposition materials (eg, oxides, nitrides, carbon materials), and the like. In some examples, coating 274 can include mirrors or partial mirrors that can be formed by sputtering a reflective material such as chromium, silver, etc. along polymer member 270 . In some examples, coating 274 can take the form of a single layer of material. Alternatively, coating 274 may comprise two or more separate and distinct layers of material (including the same or different materials).

Many methods are also conceivable for manufacturing the pressure sensor. In one exemplary manufacturing method, a cavity 168/268 can be formed in the optical fiber 124/224. This may involve etching the end region of the optical fiber using a suitable etching reagent such as HF (eg, HF in isopropyl alcohol). In some examples, the etching reagent may preferentially or faster etch the core (eg, core 160/260) of the optical fiber 124/224 than the cladding (eg, cladding 162/262). .

The method may also include placing the polymeric member 170/270 within the cavity 168/268. In some examples, this may include an ink jet process in which the polymeric material 17/270 enters directly into the cavity.

Another exemplary method for positioning the polymer members 170/270 in the cavities 168/268 is to spin-on a sacrificial layer of material (e.g., photoresist) on a dummy wafer (e.g., a dummy silicon wafer), Baking a dummy wafer having a sacrificial layer and spin-on forming a layer of polymeric material on the sacrificial layer may be included. The etched optical fiber 124/224 may be pressed onto the layer of polymeric material and the material cured (eg, heat cured, UV light cured, etc.).

Another exemplary method for positioning the polymer member 170/270 within the cavity 168/268 is to insert the etched optical fiber 124/224 into a plurality of pillars (e.g., etched pillars) formed therein. aligning and inserting onto a dummy wafer (e.g., a dummy silicon wafer) that is free of polymeric material; applying a hydrophobic or anti-stiction coating to areas desired to be free of polymeric material; dipping, spraying, printing, etc.), washing away excess polymer, baking and/or curing the material.

Another exemplary method deposits, masks, and cures a photosensitive liquid polymer layer (eg, SU-8, etc.) on the end of the optical fiber 124/224, followed by an external reflective member or coating (eg, coating 174/274). Alternatively, photosensitive dry film layers can be used to form non-glass cavity walls.

The materials that can be used for the various components of guidewire 10 (and/or other guidewires disclosed herein) and the various tubular members disclosed herein are those commonly associated with medical devices. can contain. For the sake of brevity, the following description will refer to tubular member 12 and other components of guidewire 10 . However, this is not intended to limit the devices and methods described herein, as this discussion may be applied to other tubular members and/or components of tubular members or devices disclosed herein. Not intended.

Tubular member 12 and/or other components of guidewire 10 may be metals, metal alloys, polymers (some examples of which are disclosed below), metal-polymer composites, ceramics, combinations thereof, or the like, or It can be made from other suitable materials. Some examples of suitable polymers include polytetrafluoroethylene (PTFE), ethylenetetrafluoroethylene (ETFE), fluorinated ethylenepropylene (FEP), polyoxymethylene (POM, such as DELRIN® available from DuPont). trademark)), polyether block esters, polyurethanes (e.g. Polyurethane 85A), polypropylene (PP), polyvinyl chloride (PVC), polyetheresters (e.g. ARNITEL® available from DSM Engineering Plastics), ethers or ester-based copolymers (e.g., butylene/poly(alkylene ether) phthalates and/or polyester elastomers such as HYTREL® available from DuPont), polyamides (e.g., DURETHAN® available from Bayer, or CRISTAMID™ available from Elf Atochem), elastomeric polyamides, block polyamides/ethers, polyether block amides (PEBA, e.g. available under the trade name PEBAX®), ethylene vinyl acetate copolymers (EVA), silicones , polyethylene (PE), Marlex® high density polyethylene, Marlex® low density polyethylene, linear low density polyethylene (e.g. REXELL™), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytrimethylene terephthalate, polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polypara Phenylene terephthalamide (e.g. KEVLAR®), polysulfone, nylon, nylon 12 (such as GRILAMID® available from EMS American Grilon), perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefins, polystyrene , epoxies, polyvinylidene chloride (PVdC), poly(styrene-b-isobutylene-b-styrene) (eg, SIBS and/or SIBS 50A), polycarbonates, ionomers, biocompatible polymers. Included are polymers, other suitable materials, or mixtures, combinations, copolymers, polymer/metal composites, and the like thereof. In some embodiments, the sheath can be blended with a liquid crystal polymer (LCP). For example, the mixture can contain up to about 6 percent LCP.

Some examples of suitable metals and metal alloys include stainless steels such as 304V, 304L, and 316LV stainless steels; mild steels; nickel-titanium alloys such as linear-elastic and/or super-elastic nitinol; nickel-chromium-molybdenum alloys; (e.g., UNS: N06625 such as INCONEL® 625, UNS: N06022 such as HASTELLOY® C-22®, UNS such as HASTELLOY® C276®: N10276, other HASTELLOY® alloys, etc.), nickel-copper alloys (e.g., UNS: N04400, such as MONEL® 400, NICKELVAC® 400, NICORROS® 400), nickel-cobalt- Chromium-molybdenum alloys (e.g. UNS: R30035, such as MP35-N™), nickel-molybdenum alloys (e.g., UNS: N10665, such as HASTELLOY® ALLOY B2™), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, etc.; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (eg, ELGILOY®, PHYNOX®, etc., UNS: R30003); platinum-enhanced stainless steel; titanium; combinations thereof, etc.; or other suitable materials.

In at least some embodiments, some or all of guidewire 10 is doped with, formed from, or otherwise includes a radiopaque material. can be A radiopaque material is understood to be a material capable of producing a relatively bright image on a fluoroscopic screen or another imaging technique during a medical procedure. This relatively bright image assists the user of guidewire 10 in determining its position. Some examples of radiopaque materials may include, but are not limited to, gold, platinum, palladium, tantalum, tungsten alloys, polymeric materials filled with radiopaque fillers, and the like. Additionally, other radiopaque marker bands and/or coils may be incorporated into the guidewire 10 design to achieve the same result.

In some embodiments, the guidewire 10 is provided with a degree of magnetic resonance imaging (MRI) compatibility. For example, guidewire 10, or portions thereof, may be made of materials that do not substantially distort images or produce substantial artifacts (eg, gaps in images). For example, certain ferromagnetic materials may not be suitable because they can produce artifacts in MRI images. The guidewire 10, or portions thereof, may be made of a material that can be imaged by an MRI machine. Some materials that exhibit these properties include, for example, tungsten, cobalt-chromium-molybdenum alloys (eg, ELGILOY®, PHYNOX®, etc. UNS: R30003), nickel-cobalt-chromium-molybdenum. alloys (eg, UNS: R30035 such as MP35-N™), nitinol, and the like.

It should be understood that this disclosure, in many respects, is merely illustrative. Changes may be made in details, particularly in matters of shape, size, and order of steps without exceeding the scope of the disclosure. To the extent appropriate, this may include the use of any of the features of one exemplary embodiment that are used in other embodiments. The scope of the invention is, of course, defined in the language in which the appended claims are expressed.

Claims (14)

a tubular member having a proximal region and a housing region;
An optical fiber disposed within the tubular member and extending to the housing region, the optical fiber having a distal end region with a cavity formed therein;
A pressure sensitive medical device comprising: a polymeric member disposed within the cavity to fill the cavity, the polymeric member being responsive to pressure changes; and a reflective surface disposed along a distal end of the polymeric member. 2. The pressure sensing of claim 1, wherein the proximal region of the tubular member has a first inner diameter and the housing region of the tubular member has a second inner diameter, the first inner diameter being different than the second inner diameter. medical device. 3. The pressure sensitive medical device of Claim 2, wherein the first inner diameter is smaller than the second inner diameter. 4. The pressure sensitive medical device of Claim 3, wherein the tubular member has a substantially constant outer diameter. The pressure sensing medical device of any one of claims 1-4, wherein the optical fiber has a substantially constant outer diameter. A pressure sensitive medical device according to any preceding claim, wherein one or more fiber Bragg gratings are arranged along the optical fiber. The pressure sensitive medical device of any one of claims 1-6, wherein the reflective surface comprises a coating disposed along the polymeric member. 8. The pressure sensitive medical device of claim 7, wherein the coating comprises metal. 9. A pressure sensitive medical device according to claim 7 or 8, wherein the coating is disposed on the distal end of the polymeric member. a tubular member having a proximal region and a pressure sensor housing region;
an optical fiber disposed within the tubular member and extending to the pressure sensor housing area;
the pressure sensor being defined by a cavity filled with a polymer responsive to pressure changes at the distal end region of the optical fiber; and a reflective coating disposed along the polymer distal end of the pressure sensor. A pressure-sensing guidewire. The proximal region of the tubular member has a first inner diameter, the pressure sensor housing region of the tubular member has a second inner diameter, the first inner diameter is less than the second inner diameter, and the tubular member is substantially 11. The pressure sensing guidewire of Claim 10, having a constant outer diameter. 12. A pressure sensing guidewire according to claim 10 or 11, wherein one or more fiber Bragg gratings are arranged along the optical fiber. A method of manufacturing a pressure-sensing guidewire, comprising:
forming a cavity along the distal end region of the optical fiber;
placing a polymeric member responsive to pressure changes within the cavity to fill the cavity;
A method comprising: bonding a reflective member to a distal end of a polymeric member to form a pressure sensor; and disposing the pressure sensor within a housing region of the tubular member. 14. The method of claim 13, further comprising placing one or more fiber Bragg gratings along the optical fiber.

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